Herpes Simplex is the full name of a virus best known for causing cold sores, fever blisters and the genital infections that have become widespread in the past decade. The herpes simplex viruses belong to a family of four DNA viruses that are collectively known as herpes-viruses and include those viruses which cause chicken pox, shingles, mononucleosis and encephalitis. The herpes viruses are characterized by two distinct features: they effect mainly human beings and their infection is never completely eradicated by the body's immune system. Instead, the virus lies dormant in the body and tends to become reactivated many times or many years after the initial infection, accompanied by their characteristic symptoms.
The symptoms of the herpes virus have been described for thousands of years, but recent trends show a significant rise in the number of cases. Current estimates are that between 5 and 20 million Americans have herpes and that between 300,000 and 500,000 new cases occur each year.
Within the last several decades, it has been discovered that the Herpes Simplex virus occurs in two characteristic forms, type I and type II. Generally, type I has been recognized as causing the characteristic cold sore while type II has caused the genital symptoms to be discussed herein. Currently, both types of Herpes Simplex can be found in both locations in various patients, probably resulting from various forms of personal contact. The usual symptoms of the Herpes Simplex II genital infection include painful blisters or ulcers, itching or burning, swollen lymph glands, urethritis, proctitis, fever, muscle aches and a vague feeling of being unwell.
Treatment of Herpes Simplex II is complicated by its viral character and by its characteristic residence in the nervous system rather than the blood stream. Shortly after entering the human body, the virus tends to move to the nervous system near the base of the spinal cord where it may live indefinitely. Consequently, antibodies--substances which the body normally attempts to produce in response to certain invading harmful substances--circulating in the bloodstream cannot reach the herpes virus to attack or destroy it.
The most common and troublesome characteristic of the Herpes Simplex II virus is its repeated eruption into active phases following some outside stimulus such as physical or emotional stress, the female menstrual period, sexual activity, exposure to heat or cold, use of alcohol, sunburn, physical exertion, or other similar conditions. During these active phases of the disease, the physical outbreaks cause the virus to "shed" so that close contact with another person can result in transmission of the disease. Some evidence also exists that the Herpes Simplex II virus causes cancer and if left untreated, the presence of the virus can cause the illness or death of a newborn child born during one of the outbreaks of an infected mother.
Several treatments have been developed for those affected by the disease. One recently approved treatment is the drug acyclovir marketed under the trade name ZOVIRAX. As an ointment, this medication allegedly reduces the pain and duration of outbreaks and may give some relief from the flu-like symptoms that often accompany the attacks. Nevertheless, acyclovir apparently is only useful during an outbreak and patients using the ointment must begin to use it as soon as the initial tingling symptoms appear prior to the characteristic outbreak of the lesions. Additionally, ZOVIRAX is expected to be expensive with the typical dosage for six months costing several hundred dollars.
Another, more typical approach for attacking the herpes virus is the use of a vaccine. Vaccines are typically manufactured from intact viruses which are injected into the human body in a very mild form. Ideally, the body responds to the weak form of the virus by producing specific antibodies against it. These antibodies are then sufficient to prevent outbreaks of stronger versions of the viruses with which the vaccinated person may later come in contact.
Nevertheless, vaccines normally represent preventative medicines rather than cures. Additionally, vaccines carry the risk that they may cause an occasional outbreak of the disease they are intended to prevent. For example, a few cases of polio result each year from the use of polio vaccines. Furthermore, because of the cancer risk presented by the herpes virus and the particularly serious complications and side effects of the disease, the risks of vaccination are currently considered somewhat greater than they are in the treatment of some other diseases.
Other attempts at attacking the virus have included the manufacture of subunit vaccines, i.e. vaccines made from the antigen portions of a virus. Antigens are the substances which stimulate the body to produce the appropriate antibody to combat the virus. Antigens do not contain genetic material and thus theoretically cannot cause the disease. Currently, however, the use of subunit vaccines is still in an experimental stage and some scientific critics contend that even subunit vaccines still carry the same risk of infection as normal vaccines.
Consequently, work is continuing in developing totally synthetic vaccines from genetically engineered versions of one or more of the herpes antigens, while other researchers are aiming at altering the genetic makeup of live herpes viruses so that they can safely be used to develop vaccines having a strong immune response in human beings.
There thus currently exists no acceptable vaccines for treating the herpes virus and no other medication which can be used other than to moderate the effects of the herpes outbreaks and their characteristic lesions.
It is thus an object of the present invention to provide a treatment for herpes viruses and their characteristic outbreaks and symptoms which does not carry the risks associated with vaccination, which can be used in more than topical application and which can suppress and prevent outbreaks of the characteristic symptoms of the disease instead of just moderating them once they appear.
It is a further object of the present invention to provide a treatment of the outbreaks of Herpes Simplex II viruses which suppresses the outbreak of the lesions and characteristic of this strain of the virus which consequently suppresses the shedding of active Herpes Simplex II viruses which can be transmitted by an infected party.